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प्रश्न
A zener diode is fabricated by heavily doping both p- and n- sides of the junction. Explain, why?
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उत्तर
It is a heavily doped p-n junction. As a result, the depletion region formed is very thin and the electric field of the junction is extremely high even for a small reverse bias voltage.
The I-V characteristics of a Zener diode are shown in the figure below:
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संबंधित प्रश्न
In a p-n junction diode, the current I can be expressed as
I = `"I"_0 exp ("eV"/(2"k"_"BT") - 1)`
where I0 is called the reverse saturation current, V is the voltage across the diode and is positive for forward bias and negative for reverse bias, and I is the current through the diode, kBis the Boltzmann constant (8.6×10−5 eV/K) and T is the absolute temperature. If for a given diode I0 = 5 × 10−12 A and T = 300 K, then
(a) What will be the forward current at a forward voltage of 0.6 V?
(b) What will be the increase in the current if the voltage across the diode is increased to 0.7 V?
(c) What is the dynamic resistance?
(d) What will be the current if reverse bias voltage changes from 1 V to 2 V?
Explain briefly with the help of necessary diagrams, the forward biasing of a p-n junction diode. Also draw characteristic curves.
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Explain, with the help of a circuit diagram, the working of n-p-n transistor as a common emitter amplifier.
The drift current in a p-n junction is
Find the currents through the resistance in the circuits shown in figure.
(Assume that the resistance of each diode is zero in forward bias and is infinity in reverse bias.)
In a semiconductor diode, the barrier potential offers opposition to only ______.
Zener breakdown occurs in a p-n junction having p and n both:
During the formation of a p-n junction ______.
For an ideal diode, in forward and reverse biased condition the resistance is respectively ______.
